It is well known that when an exposed color photographic silver halide light-sensitive material is color-developed, an oxidized aromatic primary amine-based developing agent reacts with a coupler to form a dye such as indophenol, indoaniline, indamine, azomethine, phenoxazine and phenazine, resulting in the formation of dye image. In the formation of magenta color images, 5-pyrazolone, cyanoacetophenone, indazolone, pyrazolobenzimidazole and pyrazolotriazole-based couplers are used.
Most of the compounds which have heretofore been in wide-spread use and extensively studies as magenta color image-forming couplers are 5-pyrazolones. It is known, however, that although dyes formed from 5-pyrazolone-based couplers exhibit high fastness against heat and light, they show an unnecessary absorption having a yellow component in the neighborhood of 430 nm, causing color-mixing.
Magenta color image-forming coupler skeletons which have been proposed to reduce the yellow component include a pyrazolobenzimidazole skeleton as described in British Pat. No. 1,047,612, an indazolone skeleton as described in U.S. Pat. No. 3,770,447, and a pyrazolotriazole skeleton as described in U.S. Pat. No. 3,725,067.
Dyes formed from 1H-pyrazolo[3,2-C]-s-triazole type magenta couplers as described in U.S. Pat. No. 3,725,067, British Pat. Nos. 1,252,418 and 1,334,515 show a reduced unnecessary absorption in the neighborhood of 430 nm in solvents such as ethyl acetate and dibutyl phthalate, and, furthermore, are superior in sharp cut-properties at the long wavelength side.
However, azomethine dyes formed from 1H-pyrazolo[3,2-C]-s-triazole type couplers show seriously low fastness against light, deteriorating seriously the performance of color light-sensitive material, particularly print-based color light-sensitive material.